The Bible claims that Jesus said a lot of things at one time that contradicted what he said at another.
It is pretty clear that what Jesus was up to was a populist reform movement within Judaism that had little or nothing to do with Gentiles. Gentiles were simply tolerated, as a part of the local climate.
Paul was the one who decided that Christianity was going to be a movement that sought to convert Gentiles. There is zero indication that any other disciples had this in mind. Jesus brother, James opposed Paul, and has been relegated to obscurity. They made him a saint after he was dead. Eventually Paul convinced Peter and that is when the Christian movement separated itself from the Jewish religion.
Without Paul, Christianity would neither have grown into a major religion, nor changed in the many ways it has since the crucifixion. It was not decided until the Council of Nicea, in AD 325. Note that Jesus said NOTHING about the Trinity. He did not mention "The Father, Me, and the Holy Ghost". The Trinity was affirmed at Nicea, a near what is today Istanbul.
What constituted the Canon of Judaism were not entirely decided upon until 200 CE, so whatever Jesus referred to mat or might not have been what is considered a compendium of Jewish beliefs today. What should be in the New Testament has never been entirely decided upon by all the various traditions of Christianity, but the Catholics seem to have reached agreement by about 400 CE. There was disagreement by many about whether to consider the Old Testament part of the Christian Canon, but, being as it includes prophesies about how Jesus was the alleged Jewish Messiah, they included it, though not in the same arrangement as Jews today consider it.
There are many instances in which Books and passages of the Bible were included and excluded by the votes of men who had never read them. Perhaps someone told them, "we have to pass it to what is in it".
Who was born on December 25th? That would be Mithra.
https://en.wikipedia.org/wiki/Mithraic_mysteries The date was chosen because it is the date at which the days begin to get observably longer: the Sun is returning. Being as Mirthraism was a Persian religion, and it mostly excluded women, it is pretty obscure today, as the Muslims regarded it as idolatrous, which, of course, it clearly was. It was the most popular religion among the Rokman legions, who, of course, were mostly NOT Roman, especially in the Eastern part of the Empire. At the time of Jesus actual birth, we hear that shepds were about, tending their flocks, and of course that would require vegetation. There is not much reason for a shepherd to tend his sheep near Bethlehem in December, as there would be nothing for said sheep to eat. Jesus was probably born in the Spring, but the Dec. 25th date was near rather a lot of popular holiday celebrations in the Roman Empire, so that seems to be why that date was selected.
And Jesus was said to have been born in times of King Herod, who died in 4 BCE, so Jesus lived, not from 1 CE to 33 CE, but from somewhere around 4-8 BCE and 25-29 CE. The Bible does describe historical events, but not precisely or well or in any way completely. There si doubt that there was an actual settlement at Nazareth at the time of Jesus' life. There is evidence of settlement before 700 BCE and after 300 CE, but towns were destroyed and not rebuilt until centuries had passed.
Christianity was spread to India and Ethiopia by Egyptian and Syrian missionaries, and their sermons contained great amounts of Paul, although Paul did not venture to either place. Most Indian Christians are descendants of people converted by European missionaries, by the way, and are about 2.3% of the Indian population. It ranks third, after Hinduism (79%) and Islam (14%). India is the birthplace of even more religions than the "Holy Land".
The Church changed in many ways during the time of Paul until the Council of Nicea. It was decided that the communion wine would actually change into human blood. Humans are not kosher, and drinking actual blood and of course, cannibalism and anathema to the Jewish traditions. The Jewish Scholar Maimonides described in great detail what was unkosher about Christianity of his time (1135-1204).
https://en.wikipedia.org/wiki/MaimonidesHe was born in Córdoba, Spain, and lived in Morocco, Egypt and in other places. He is honored with a plaque in the House of Representatives. I doubt that he commentaries on Christianity were known at the time. Jews sort of deliberately fail to recall commentaries on Christianity than are critical. It has been a pretty good idea to do this. Maimonides had rather a long list of Christian beliefs that he considered heretical, untrue and trayf. I read his works in Spanish, but I am sure that it is available in English online. He is somewhat difficult to wade through, as he likes long sentences. Some of what I have read of his works were written in Arabic and Hebrew, so perhaps the translator is to blame. Maimonides is particularly critical of the misinterpretation of what a Messiah is, and how the Trinity is an anathema. He is a strict monotheist.